毕业设计基于单片机的环境温湿度检测系统

河南理工大学万方科技学院本科毕业论文I摘要环境温湿度检测系统是日常生活、工业生产和农业管理中广泛使用的一种设备。该设备具备以下主要功能：实时检测出环境中的温度和湿度参数值，并显示出来，根据设定的报警限予以报警指示，可以和上层控制器通信。随着单片机的大规模应用，单片机在检测系统中也越来越多的被使用。本设计以AT89S52这款低功耗、高性能、在系统编程的8位单片机为系统控制处理核心，由单总线数字温湿度传感器DHT11、数码管显示屏、LED与蜂鸣器、通信串口和按键控制输入等五个部分组成，从而实现环境问世的监测系统的主要功能。后期的探索设计——换用红外遥控控制和LCM为显示屏、外加时钟和存储芯片、增加照度检测电路，极大地提升了系统的性能，使系统不仅可以检测并显示环境温度、湿度和照度变量，而且可以按照时间顺序存储适量的数据。此外，系统有降压整流和稳压滤波电路，可用交流市电（220V）、各种安全直流电（5~24V）、太阳能电池等为系统供电，并且可以存储少量电能（900mAh）,因此，系统有较宽的工作电压，可满足多种应用场合。本设计由Protel画出了电路原理图和PCB图，并由此完成了硬件的制作，使用C51语言对单片机进行编程控制，并模块化仿真，最后通过综合调试，符合预期的设计要求。关键词：AT89S52单片机DHT11传感器PCB设计温湿度检测河南理工大学万方科技学院本科毕业论文IIAbstractEnvironmenttemperatureandhumiditydetectionsystemisakindofequipmentwhichiswidelyusedindailylife,industrialproductionandagriculturalmenagement.Theequipmenthasfollowingmainfunction:detectingthetemperatureandhumidityparametersintheenvironmentreal-timeanddisplaythem,givingalarmindicationaccordingtothesetlimits,andbeingabletocontactwithuppercontroller.WiththeSCMusedlarge-scalely,theSCMismoreandmoreusedindetectionsystem.Thisdesign,usesthe8-bitSCMnamedAT89S52,whichhasalotofadvantagessuchaslow-powerdissipation,high-performanceandISP,andmadeupoffiveparts:single-wiredigitaltemperatureandhumiditysensor,digitrondisplay,LEDandbuzzer,serialcomunicationsandkeysinput,thusperformthefunctionofenvironmenttemperatureandhumiditydetectionsystem.Theexplorationdesigninlaterstage,includinginfraredremotecontrolandLCMdisplay,clockandmemorychips,andilluminationdetectioncircuit,immenselypromotesthepropertyofthesystem,makesitnotonlydetecteanddisplaythetemerature,humidityandillumination,butalsostoresomedatainorderoftime.Inaddition,withstep-downrectifierandstabilivoltfiltercircuit,thesystemcanuseutilitypowerAC220V,differentsafetyDC5~24V,solarbatterytosupplypower,andstoresomeelectricenergyabout900mAh,sothatithasawidepowersupplyvoltageandmeetsdifferentapplicationplaces.ThedesigngivesthecircuitdesignschematicsandPCBdiagramwithProtel,andcompletesthehardwarepartoftheproduction,andusesC51languagesystemtoaccomplishthecontrolprogramofSCM,andsimulateseverypartsuccessfully.Throughthesyntheticaldebugging,thedesignachievestherequireddesigns.Keywords:AT89S52SCM,DHT11sensor,serialcommunication,temperatureandhumiditydetection,PCBdesign河南理工大学万方科技学院本科毕业论文i目录第一章前言.................................................................................................................11.1设计的目的意义调查.......................................................................................11.2设计的市场现状分析.......................................................................................21.3设计的内容要求说明.......................................................................................31.4设计的实施方案构想.......................................................................................4第二章硬件的设计.........................................................................................................52.1单片机的选用...................................................................................................52.2传感器的选用...................................................................................................72.2.1初期设计.................................................................................................72.2.2最佳方案.................................................................................................82.2.3电路设计.................................................................................................92.3数码管驱动电路设计.....................................................................................102.3.1数码管的选用.......................................................................................102.3.2驱动电路的设计...................................................................................102.4报警电路设计..................................................................................................122.4.1蜂鸣器驱动电路...................................................................................132.4.2LED驱动电路.........................................................................................132.5控制输入电路设计..........................................................................................142.6串口通信电路设计.........................................................................................162.7稳定电源电路设计.........................................................................................172.8系统三大部分的PCB设计.............................................................................182.8.1系统主体部分PCB设计.......................................................................192.8.2串口通讯PCB设计...............................................................................202.8.3稳压电源部分PCB设计........................................................................21第三章程序的设计.......................................................................................................233.1程序功能描述、单片机内部资源分配和程序流程图.................................233.1.1程序功能描述.....................................................................................233.1.2单片机内部资源分配——两个定时器的分工..............